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Whole Foods & Diets
Food selection is critical for two reasons -- proper nutrition and avoidance of toxics.
First we explore proper nutrition. The focus here is on eating the substances the body needs, and ensuring they are assimilated for cellular use. Cells are where nutrients are utilized, so ultimately cellular health is key to bodily health.
Supplements are often a key to optimal health (and please see this site's page on supplements), but they are not a substitute for whole foods. Nobody lives on supplements alone (except for the comatose on life-support), and the nutritional emphasis should be first on healthy whole foods. Furthermore, good eating is enjoyable, doubly so when we know our chosen foods will promote optimal health.
We can approach food selection according to single foods, or according to published diets. Let us talk about diets first.
Here the interest is not weight-loss diets, but instead diets for optimal general health. While millions of Americans need weight-loss, and therefore pursue weight-loss diets and associated supplements, spending billions of dollars every year, the fact is that a diet for health will (eventually) bring about desired weights for all but a tiny fraction of overweight people. The diet craze in America is fueled by simple overeating and poor food selection combined with lack of exercise.
Some overweight people may require medical intervention to deal with obesity, and even perhaps the radical approach of stomach or intestinal resection, but it is presumed here that obese people dealing with a medical obesity condition will be seeking medical care. We do not need to explore such situations as involve medical obesity, other than to note that Americans are the most obese people on the planet, and treating obesity is a major public health issue.
Healthy diets for most people are not hard to choose, but the news media make clear that diet choices are very controversial. Advocates of various well-known diets are in obvious dispute. Controversies rage in the medical literature and are well-publicized.
Here are the major types of diets and a brief description of their differences.
- Mediterranean diet -- refer to Walter Willett of the Harvard Medical School -- Willett WC, Sacks F, Trichopoulou A, et al. "Mediterranean diet pyramid: a cultural model for healthy eating." Am J Clin Nutr. 1995;61(suppl 6):14025-1406S. Also see http://www.drpressman.com/Library/TraditionalMediterraneanDiet.htm -- "The Traditional Mediterranean Diet:
The Scientific Basis for its Health Benefits" -- "traditionally plant-based diets in which red meat is consumed only a few times a month. Fruits, vegetables, bread, cereals, legumes, and nuts are eaten in abundance, and red wine is a part of everyday life. Chicken and fish appear on the table in low to moderate amounts, and dairy is consumed mostly in the form of yogurt and cheese - and usually as a condiment."
by Kevin C. Vigilante, MD, MPH, and Mary M. Flynn, PhD, RD
International Journal of Integrative Medicine, Vol 3, No 2, Aug/Sep 2001.
- Ornish low fat diet -- see Dean Ornish, M.D., Reversing Heart Disease (New York: Random House, 1990). For his website, see Ornish diet. By radical reduction of dietary fat, Ornish claims that arterial clogging is diminished and in some cases reversed. Ornish emphasizes nutrition, exercise, stress management, and love & intimacy, for optimum health.
- Atkins low carbohydrate diet -- see Robert C. Atkins, Dr. Atkins' New Diet Revolution, 1997 and later editions. On the web, see Atkins Center. Controversial for more than 20 years, the Atkins diet advises reducing carbohydrate intake to low levels (in the initial stages, to less than 20 grams per day), which induces burning of fats (even to the level of ketosis, the production of ketones as fat-combustion by-products which are then excreted). Atkins claims (and recently confirmed at least in part by new studies) that weight loss ensues, and cholesterol levels drop.
- Zone diet -- see Zone Diet -- Summary. The Zone diet pioneered by Dr. Barry Sears is directed toward controlling insulin levels (to be discussed below). The name "Zone" refers to keeping insulin levels within a narrow zone of concentrations. As described by Sears, "The Zone Diet is a life-long hormonal control strategy. ... having more fat in the diet is important for reducing insulin, especially since it does not stimulate insulin production. The best type of fat is monounsaturated fat, like olive oil, guacamole, almonds, and macadamia nuts." Typically, the diet involves restricting the diet to low-animal-fat protein sources, and fruits and vegetables (including vegetable oils), but avoiding low-fat grains in such forms as pasta and bagels. As discussed next, pasta and bagels increase blood insulin levels and bring about harmful effects.
The above diets conflict in substantial ways -- generally, the Atkins diet involves high fat intake, directly contrary to a low-fat diet advocated for 2 decades as a way to reduce or postpone heart disease. On the low-fat diet, however, most Americans binged on carbohydrates, and particularly large amounts of table sugar (sucrose). The consequence has been large increases of insulin levels soon after eating (to process the increased glucose concentration in the blood, as sucrose is digested into its components of fructose and glucose), and the high insulin spike induces conversion of glucose to fat in the liver, and increases cholesterol production. As a result, the low fat diet resulted in increasing obesity in America. If good fats such as fish oil and vegetable oils (including olive oil) that contain the desirable omega-3 fatty acids are reduced in low fat diets, such diets even increase the risk of heart disease!
To be complete, however, we note that Ornish's low fat diet never recommended replacing fat with table sugar. That replacement came as a result of the American penchant for sweets as a substitute for tasty fats (and obliged by the food production companies interested in selling snacks).
Cutting across all discussion of carbohydrates is the subject of glycemic indexing. This index is a measure of the insulin response to different foods with their different kinds and amounts of carbohydrate content. Simple glucose (obtained from the sucrose in table sugar) is given the relative index value of 100. Other foods are rated in comparison to glucose, with respect to how much insulin appears in the blood afterward.
It is now becoming widely recognized that a healthy diet contains foods with a low glycemic index. Such foods elevate blood glucose levels only slowly after a meal, so that the "sugar crash" from snack foods is avoided, and the simple sugar content is assimilated for burning at the cellular level and not converted into fat in the liver. An informative source for information about glycemic indexing is Jennie Brand-Miller, Ph.D. et al., The New Glucose Revolution (New York: Marlowe and Co., 2003). On the web, look for the Glycemic Index On-Line, and the Glycemic Research Institute.
While a comparative study has not been done on the four diets listed above (Mediterranean, Ornish, Atkins, and Zone), benefits from each can probably be maximized by selecting low glycemic index foods. Also, choose foods with vegetable fats and fish oils as opposed to land animal fats (vegetable fats and fish oils contain the desirable omega-3 fatty acids).
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